The present invention concerns a device for ensuring safety by preventing mechanically raised and lowered components from crashing down when a motor or transmission fails. An example is a gate that rolls up and down subject to a shaft.
Mechanically raised and lowered components have as a rule been prevented from crashing down in the event of failure by automatic brakes or springs. In many applications, however, roll-up gates for example, these measures are considered unsatisfactory. Safety-ensuring devices in the form of electromagnetically activated interlocking clutches are accordingly known. They are independent and not part of the transmission. They have a drawback in that, especially when the components being raised and lowered are heavy, such clutches must accommodate powerful sudden forces, which subject its components to particularly severe materials stress.